twitter icon facebook icon youtube icon instagram icon

Stories from the valley

7 El Niño Questions and Answers

Contributed by Jim Morris


Mike Anderson- 8315I had the chance to visit with Mike Anderson, who has served as State Climatologist with the Department of Water Resources since 2007. Assessing long-term weather is his forte. As the drought tightens its grip on our state, there’s hope that the El Niño weather phenomenon will bring relief. Here are questions and answers on what he thinks may lie ahead in a most critical fall and winter:

1) What is the current likelihood that we will have an El Niño in California this fall and winter?

A:  Right now we’re in a developing El Niño, which is strengthening. We need it to continue and forecasts call for it to continue through the later part of fall or early winter before it peaks. We would ideally like it if it got into winter before it peaked – hopefully strong as well. The Climate Prediction Center puts out the probability of the conditions being in place based on their forecast models. Right now their forecast models suggest a 90 percent probability that the event will be in place through the winter.

2) What are some of the major indicators to be in place for an El Niño?

A: The main elements within the climate system are sea surface temperatures in the tropical Pacific Ocean. They’re looking for those temperatures to be nearly two degrees warmer than the average for that time of year and persist for at least six months. The warmer the temperature, the increased chance to be in the strong El Niño category.

3) Some are calling this a potential Godzilla of all El Niños in terms of its impact. What is your feeling about its strength if indeed it does arrive?

A: There have been some more of my enthusiastic colleagues that are watching the trajectory of the warming, saying that this warming could be on pace with the 1998 El Niño event which was the largest in the observed record which goes back to 1950. I think they’re looking at it and extrapolating from there. I tend to take a more wait and see attitude, because we have had events in the past where it peaks early and starts to fade in the fall, like what happened in water year 1992 (fall 1991).

4) Some of the reports indicate there’s a greater likelihood for increased rain in Central and Southern California. Is this something you concur with?

A: When the Climate Prediction Center looks at the precipitation and temperature outcomes associated with an El Niño event, the strongest correlations come in Southern California with a wet response. Northern California tends to be a wash because we’re right in the transition zone between wet and dry. Their depictions tend to show that gradient of wet in Southern California fading towards drier in the Pacific Northwest, and that’s why it’s very hard to tell what happens in Northern California. It depends on where that boundary is going to come in.

5) What’s your personal perspective on all of this?

A: Hopeful, but still taking a ‘wait and see’ approach to how it comes out. We will track this closely.

6) When will there be a definitive forecast of a 100 percent chance of El Niño?

A: I don’t that we ever get there, but some of the key timeframes are the transition into winter – end of December into January. With El Niños, winter may take a little bit to get started but once it does, it really kicks in after the New Year and then it’s usually January, February and March that are really wet.

7) In your experience as a climatologist, how dire do you feel this drought is? How much do we need something to break this dry pattern up?

A: This is what you might call a generational drought – something that we haven’t seen in a generation. We’re getting into territory that gets within some of the historic droughts in our state including 1976-77 and 1928-34. We’re definitely in that realm and definitely looking for relief.